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91.
92.
Recent data obtained by LEP1 are discussed and their potential implication for the existence of a Z particle. This letter advocates that this fits within the basic tenet of an SU(2)×SU(2) extended theory of the standard model of electroweak interactions. This extended electroweak model is motivated by nonabelian electrodynamics that provides an effective calculus for nonlinear optics.  相似文献   
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94.
Laboratory observations that suggest a frequency anisotropy in the direction of the Leo constellation of δν/ν⩾10-6 can be interpreted in terms of a nonzero photon mass m γ≅10-65 g. If one then accepts the theory of light (considered as real Maxwellian waves and photons simultaneously) of Einstein and de Broglie, the experimental justification of the existence of real Maxwellian displacement currents implies the existence of mγ>0 and of a vacuum dissipative mechanism which can interpret a part (or the totality) of Hubble's cosmological red shift  相似文献   
95.
By considering the irreducible representations of the Einstein group (the Lie group of general relativity), Sachs [1] has shown that the electromagnetic field tensor can be developed in terms of a metric q , which is a set of four quaternion-valued components of four-vector. Using this method, it is shown that the electromagnetic field vanishes [1] in flat spacetime, and that electromagnetism in general is a non-Abelian field theory. In this paper the non-Abelian component of the field tensor is developed to show the presence of the B (3) field of the O(3) electrodynamics, and the basic structure of O(3) electrodynamics is shown to be a sub-structure of general relativity as developed by Sachs. The extensive empirical evidence for both theories is summarized.  相似文献   
96.
It is possible to prepare carbon-based analogues of the Merrifield resin by electrochemical reduction of diazonium salts or oxidation of aryl acetates on high specific surface area carbon felts. These modified felts can undergo further reactions: nucleophilic substitution, Suzuki reaction, and finally reductive electrochemical cleavage, taking advantage of the conductivity of the carbon felt. This provides a simple example of the possible use of electrochemistry in combinatorial synthesis.  相似文献   
97.
Texture-related features of water intrusion in hydrophobised MCM-41 silicas render these materials especially suitable for energy dissipation in mechanical dampers.  相似文献   
98.
A convenient and efficient procedure for the synthesis of 4-arylchromenes, thiochromenes, and related heterocycles via a four step-sequence has been developed. The first three steps, which involve hydration of alkynes, hydrazones formation, and their Pd-coupling with ortho substituted aryl halides, furnished stereoselectively Z-trisubstituted olefins without any purification of the intermediates generated in each stage. These latter proved to be suitable precursors, in the last step, for the synthesis of the desired heterocycles of biological interest.  相似文献   
99.
The surface of meltblown poly(butylene terephthalate) (PBT) nonwoven was modified by photochemistry using the photolinker O‐succinimidyl 4‐azido‐2,3,5,6‐tetrafluorobenzoate for the introduction of activated ester functions and then coupling of molecular probes or biomolecules. Approximately 4000 pmol of (L )‐4,5‐[3H]‐lysine was fixed per PBT sample (1.13 cm2) and measured by liquid scintillation counting. The method consisted in a two‐step process: (a) coating of the clip (0.05 mg/sample) on the fibrous surface of the PBT followed by UV irradiation (30 min, 254 nm) and (b) coupling of amine‐terminated molecules (10?3 M in phosphate buffer–CH3CN [1/1, v/v], 20 h). Moreover, about 2000 pmol of 3H‐lysine can be immobilized on the PBT surface after UV irradiation (without clip) by aminolysis reactions with the created oxygenated functions. The derivatizations (via the clip and UV irradiation only) were stable after long‐term heating at 100 °C in water or under steam‐sterilization conditions. They induce neither modifications of the nonwoven morphology nor cytotoxicity. This method was applied for the grafting of peptides Gly‐Arg‐Gly‐Asp‐Ser and Gly‐Gly‐Gly‐Gly‐Gly to perform blood filtration experiments and to retain the leukocytes. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011  相似文献   
100.
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